Installation

SYSTEM ONE – TERMINAL FUNCTIONS
POS – 13.8 Vdc
NEG – 0 Vdc
TC1 (at Master Station)
��Connection point for TC wires from Room Stations where security voice is required.
��Approximately 0Vdc with system at rest.
��Outputs approximately 12Vdc for duration of communication and security voice when initiated from
Master.
��Inputs approximately 12Vdc for duration of communication or chime when initiated from another
station.
TC2 (at Master Station)
��Connection point for TC wires from Room Stations where security voice is not required.
��Approximately 0Vdc with system at rest.
��Outputs approximately 12Vdc for duration of communication but not for security voice when
initiated from Master.
��Inputs approximately 12Vdc for duration of communication or chime, when initiated from another
station.
TC (at Room and Door Stations)
��Approximately 0Vdc with system at rest.
��Outputs approximately 12Vdc at the initiating station for the duration of communication or chime.
��Inputs approximately 12Vdc for duration of communication, chime or security voice (where
applicable) when initiated from another station.
VLC
��Outputs specific voltage levels with reference to 1/2 supply at the initiating station.
��Inputs specific voltage levels with reference to 1/2 supply at receiving stations.
��Voltage levels are related to specific functions – see following calculations and table.
1. Measure the supply voltage across the POS and NEG terminals of the station being checked.
2. Divide the measured voltage by 2 to give a value representing 1/2 supply. Note this value as it is
used as a reference in the following table.
3. Measure the VLC terminal with respect to NEG while pressing and holding a button at the
station being measured.
4. The measured VLC value for the button being pressed should be very close (+/- 0.1V) to the
voltage outlined in the following table.
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